fix using static variable hack

Author: smnwttbr

Packages/com.unity.inputsystem/InputSystem/Editor/AssetEditor/InputBindingPropertiesView.cs

@@ -149,7 +149,7 @@ private static void DrawMatchingControlPaths(List<MatchingControlPath> matchingC
         private void DrawMatchingControlPaths()
         {
             bool controlPathUsagePresent = false;
-            List<MatchingControlPath> matchingControlPaths = MatchingControlPath.CollectMatchingControlPaths(m_ControlPathEditor.pathProperty.stringValue, showMatchingLayouts, ref controlPathUsagePresent);
+            List<MatchingControlPath> matchingControlPaths = MatchingControlPath.CollectMatchingControlPaths(InputControlPathEditor.pathProperty.stringValue, showMatchingLayouts, ref controlPathUsagePresent);
             if (matchingControlPaths == null || matchingControlPaths.Count != 0)
             {
                 EditorGUILayout.BeginVertical();

Packages/com.unity.inputsystem/InputSystem/Editor/ControlPicker/InputControlPathEditor.cs

@@ -31,7 +31,7 @@ public InputControlPathEditor(SerializedProperty pathProperty, InputControlPicke
             if (pathProperty == null)
                 throw new ArgumentNullException(nameof(pathProperty));
             Debug.Log($"New Path Property on {pathProperty.serializedObject.targetObject.GetInstanceID()}");
-            this.pathProperty = pathProperty;
+            InputControlPathEditor.pathProperty = pathProperty;
             this.onModified = onModified;
             m_PickerState = pickerState ?? new InputControlPickerState();
             m_PathLabel = label ?? new GUIContent(pathProperty.displayName, pathProperty.GetTooltip());
@@ -159,8 +159,8 @@ private void ShowDropdown(Rect rect, Action modifiedCallback)
                     m_PickerState,
                     path =>
                     {
-                        Debug.Log($"Saving path to property on {pathProperty.serializedObject.targetObject.GetInstanceID()}");
                         pathProperty.stringValue = path;
+                        pathProperty.serializedObject.ApplyModifiedProperties();
                         m_PickerState.manualPathEditMode = false;
                         modifiedCallback();
                     });
@@ -183,7 +183,12 @@ private void SetExpectedControlLayoutFromAttribute(SerializedProperty property)
                 SetExpectedControlLayout(attribute.layout);
         }
 
-        public SerializedProperty pathProperty { get; }
+        // This static variable is a hack. Because the editor is rebuilt at unpredictable times with a new serializedObject, we need to keep updating
+        // This variable with most up to date serializedProperty, so that the picker dropdown can access the correct serializedProperty.
+        // The picker dropdown is a separate window and does not have access to the changed serializedObject reference.
+        // This is a temporary solution until the InputControlPathEditor is converted to UITK or there is away to have a stable, persistent serializedObject backing this editor.
+        // This property will be shared among multiple asset editor windows.
+        public static SerializedProperty pathProperty { get; private set; }
         public Action onModified { get; }
 
         private GUIContent m_PathLabel;